Rosanna Maria Viglialoro

Augmented reality visualization of deformable tubular structures for surgical simulation

Surgical simulation based on augmented reality (AR), mixing the benefits of physical and virtual simulation, represents a step forward in surgical training. However, available systems are unable to update the virtual anatomy following deformations impressed on actual anatomy.

Tactile Augmented Reality for Arteries Palpation in Open Surgery Training

Palpation is an essential step of several open surgical procedures for locating arteries by arterial pulse detection. In this context, surgical simulation would ideally provide realistic haptic sensations to the operator. This paper presents a proof of concept implementation of tactile augmented reality for open-surgery training. The system is based on the integration of a wearable tactile device into an augmented physical simulator which allows the real time tracking of artery reproductions and the user finger and provides pulse feedback during palpation. Preliminary qualitative test showed a general consensus among surgeons regarding the realism of the arterial pulse feedback and the usefulness of tactile augmented reality in open-surgery simulators.

Augmented Reality Simulator for Laparoscopic Cholecystectomy Training

Augmented reality (AR) simulation, mixing the benefits of virtual and physical simulation, represents a step forward in surgical education. In preliminary studies, we demonstrated the possibility to correctly show AR information in case of deformations of the physical models thanks to the integration of electromagnetic (EM) tracking technologies into the simulation environment. In this paper, we describe an innovative AR simulator for laparoscopic cholecystectomy and in particular for the isolation of the cystic duct and artery, the most crucial phase of the intervention. The proposed simulator allows the AR visualization of these deformable tubular structures, which are covered by connective tissue and thus are difficult to identify. Moreover it provides an acoustic feedback as an alarm to the user in case of potential surgical errors.

Patient-specific ultrasound liver phantom: materials and fabrication method

PurposeAn anatomically realistic ultrasound liver phantom with tissue-specific distinct signal properties is needed for training of novices in diagnostic and interventional procedures. The main objective of this work was development and testing of a new durable liver ultrasound training phantom for use with a hybrid simulator.MethodsA liver ultrasound phantom was fabricated in four main phases: materials selection, segmentation of CT images and realization of 3D models, vessel and lesion realization, and final assembly with silicone casting. Silicone was used as basic material due to its durability and stability over time. Several additives were analyzed and mixed with the polymer to reproduce the echogenicity of three simulated soft tissue types: parenchyma, lesions, and veins.ResultsCysts and vessel trees appear anechoic in the B mode ultrasound images when realized with pure silicone. The liver parenchyma, hypoechoic, and hyperechoic lesions were realized with different concentrations of graphite and Vaseline oil to increase their relative echogenicity. These materials were successful for creation of an ultrasound liver phantom containing simulated blood vessels and lesions.ConclusionThe phantom reproduces the human liver morphology and provides vessels and lesions ultrasound images with recognizable differences in echogenicity. The speed of sound in the simulated materials is inaccurate, but the problem can be overcome via software adjustment in a hybrid simulator.

Wearable Tactile Interfaces Using SMA Wires

This paper describes the use of SMA (Shape Memory Alloys) wires to develop wearable tactile interfaces. In this early work, the wearable interface consists of a nylon glove with thin SMA wires stitched on it. The SMA wires provide a tunable pressure sensation when they are electrically actuated appropriately. Each wire is anchored to the fingernail-shaped support via screw clamps to ensure both the electrical continuity of the connections and to efficiently transmit the contraction force on the fingertip. A suitable actuation system of SMA wires has been designed and implemented on an Arduino Uno microcontroller to prevent their overheating. The knowledge of SMA wires mechanical, thermal and electrical properties allowed the implementation of a proper actuation strategy. The interface was characterized in terms of response time and force felt on the fingertip. Ten subjects have positively evaluated the interface in terms of wearability, comfort and tactile sensations. This work paves the way for the development of highly wearable tactile interfaces to be integrated in Virtual Reality (VR) and Augmented Reality (AR) environments.

A Microsoft HoloLens Mixed Reality Surgical Simulator for Patient-Specific Hip Arthroplasty Training.

Surgical simulation can offer novice surgeons an opportunity to practice skills outside the operating theatre in a safe controlled environment. According to literature evidence, nowadays there are very few training simulators available for Hip Arthroplasty (HA).

Proof of Concept: Wearable Augmented Reality Video See-Through Display for Neuro-Endoscopy.

In mini-invasive surgery and in endoscopic procedures, the surgeon operates without a direct visualization of the patient’s anatomy. In image-guided surgery, solutions based on wearable augmented reality (AR) represent the most promising ones. The authors describe the characteristics that an ideal Head Mounted Display (HMD) must have to guarantee safety and accuracy in AR-guided neurosurgical interventions and design the ideal virtual content for guiding crucial task in neuro endoscopic surgery. The selected sequence of AR content to obtain an effective guidance during surgery is tested in a Microsoft Hololens based app.

Robust laparoscopic instruments tracking using colored strips

To assist surgeons in the acquisition of the required skills for the proper execution of the laparoscopic procedure, surgical simulators are used. During training with simulators it is useful to provide a surgical performance quantitative evaluation. Recent research works showed that such evaluation can be obtained by tracking the laparoscopic instruments, using only the images provided by the laparoscope and without hindering the surgical scene. In this work the state of the art method is improved so that a robust tracking can run even with the noisy background provided by realistic simulators. The method was validated by comparison with the tracking of a “chess-board” pattern and following tests were performed to check the robustness of the developed algorithm. Despite the noisy environment, the implemented method was found to be able to track the tip of the surgical instrument with a good accuracy compared to the other studies in the literature.